Split a PDF by Size So It Fits Email and Upload Limits
Divide an oversized PDF into parts that each stay under Gmail, Outlook, or portal size caps — automatically.
Why this workflow matters
Compression alone cannot always solve a size cap: a 60MB scan squeezed below 10MB turns to mush, and some portals cap uploads at 5MB or less no matter what the document contains. Splitting by size takes a different route — the document stays at full quality, but is divided into consecutive parts (pages 1–40, 41–78, and so on) that each fit the limit you choose. Recipients read part one, then part two; nothing is lost and nothing is degraded. It is the honest fix when quality matters more than a single attachment.
Who this is for
- Anyone stuck under Gmail’s 25MB or Outlook’s 20MB cap
- Applicants whose single-file portal limits defeat compression
- Teams sharing long, high-quality scans internally
Step-by-step: split pdf by size
Upload the large PDF
Drop in the file that is too big to send whole.
Pick a size limit
Choose 25MB for Gmail, 20MB for Outlook, or the portal’s stated cap.
Split
Parts are built in page order, each measured against the real saved file size.
Send the parts in order
Download the ZIP and attach part-1, part-2, … in sequence.
Practical tips
- Leave headroom: email encoding inflates files by roughly a third, so pick a limit about a quarter below the stated cap.
- Tell the recipient how many parts to expect so they know the set is complete.
- Try compression first if the limit is generous — one file is always easier than five.
Common problems
A single page exceeds the limit on its own
A page cannot be divided; compress the document first or send that page separately through a file-sharing link.
Parts arrived out of order
Filenames are part-1.pdf, part-2.pdf in page order — re-sort by name before forwarding.
FAQ
How is splitting by size different from compressing?
Compression shrinks the whole file, with some quality cost. Splitting keeps every page at original quality and divides the document into parts that each fit the limit.
Will the parts still open as normal PDFs?
Yes — every part is a complete, standalone PDF with its pages copied unchanged. Open, print, and forward them like any PDF.
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Ready to split pdf by size?
Open Split PDF by Size and follow the steps above. No account required for core use.